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A064922
Number of iterations in A064920 to reach a prime.
4
0, 0, 1, 0, 2, 0, 1, 1, 3, 0, 3, 0, 2, 1, 2, 0, 2, 0, 2, 2, 4, 0, 4, 2, 3, 1, 4, 0, 4, 0, 1, 1, 3, 1, 3, 0, 3, 2, 4, 0, 4, 0, 3, 1, 5, 0, 3, 1, 3, 1, 3, 0, 3, 2, 3, 3, 5, 0, 3, 0, 2, 2, 2, 1, 3, 0, 3, 3, 3, 0, 4, 0, 4, 1, 5, 1, 3, 0, 3, 1, 5, 0, 3, 3, 4, 1, 3, 0, 5, 1, 4, 2, 4, 1, 4, 0, 3, 1, 5, 0, 5, 0, 3, 3, 4
OFFSET
2,5
COMMENTS
a(p) = 0 for all primes p.
LINKS
EXAMPLE
a(18) = 2 as A064920(A064920(18)) = A064920(8) = 5 = A064921(18).
PROG
(PARI) gpf(n)= { local(f); f=factor(n)~; return(f[1, length(f)]) } { for (n=2, 1000, m=n; a=0; while (!isprime(m), g=gpf(m); m=m / g + g - 1; a++); write("b064922.txt", n, " ", a) ) } \\ Harry J. Smith, Sep 29 2009
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Oct 14 2001
STATUS
approved